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Recently Released Special Editions

Micromounts

Friday, 30 June 2023 01:30 PM

Introducing the "Micromounts" gallery which is part of our Special Edition galleries. This gallery contains mineral specimens for sale including polybasite, proustite, pseudobrookite, pyrite, and pyromorphite and more from places like Las Chispas mine, Arizpe, Sonora, Mexico, Cobalt dist., Ontario, Canada, Topaz Mountain, Thomas Range, Juab Co., Utah, United States, French Creek mines, Chester Co., Pennslyvania, United States, and Bunker Hill mine, Shoshone Co., Idaho, United States.

SOLD
Polybasite - 61819
Polybasite - 61819

Polybasite

#61819
Locality
Las Chispas mine, Arizpe, Sonora, Mexico 
Formula
Cu(Ag,Cu)6Ag9Sb2S11 
Availability
Sold
Size
Micromount 
Tagged
sulfide , copper , silver  

Nicely mounted crystal plate 1.2cm across with an overgrowth of Pyrite. There is also a great, deep red, prismatic crystal of Pyrargyrite or Proustite along the side.


Polybasite

Formula
Cu(Ag,Cu)6Ag9Sb2S11 
Crystal System
Monoclinic 
Crystal Habit
Massive - Granular, Granular, Pseudo Hexagonal 
Cleavage
Poor, None, None 
Luster
Sub Metallic 
Color
black, dark ruby red 
Streak
reddish black 
Class
Monoclinic - Prismatic 
Fracture
Uneven 
Hardness
2.5-3 
Mineralpedia
View Polybasite
On Dakota Matrix
Previously Sold Polybasite
On Dakota Matrix
Other Available Polybasite
WebMineral
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Mindat
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SOLD
Polybasite - 61824
Polybasite - 61824

Polybasite

#61824
Locality
Las Chispas mine, Arizpe, Sonora, Mexico 
Formula
Cu(Ag,Cu)6Ag9Sb2S11 
Availability
Sold
Size
Micromount 
Tagged
sulfide , copper , silver  

There are numerous, less than 1mm, silvery striated crystals on this matrix 2 x 1.5cm.


Polybasite

Formula
Cu(Ag,Cu)6Ag9Sb2S11 
Crystal System
Monoclinic 
Crystal Habit
Massive - Granular, Granular, Pseudo Hexagonal 
Cleavage
Poor, None, None 
Luster
Sub Metallic 
Color
black, dark ruby red 
Streak
reddish black 
Class
Monoclinic - Prismatic 
Fracture
Uneven 
Hardness
2.5-3 
Mineralpedia
View Polybasite
On Dakota Matrix
Previously Sold Polybasite
On Dakota Matrix
Other Available Polybasite
WebMineral
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Mindat
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SOLD
Proustite - 61898
Proustite - 61898

Proustite

#61898
Locality
Cobalt dist., Ontario, Canada 
Formula
Ag3AsS3 
Availability
Sold
Size
Micromount 
Tagged
sulfide , silver  

Deep red micro crystals.


Proustite

Formula
Ag3AsS3 
Crystal System
Trigonal 
Crystal Habit
Massive, Crystalline - Poor, Blocky 
Cleavage
None, None, None 
Luster
Sub Metallic 
Color
vermilion, reddish gray 
Streak
vermilion red 
Class
Trigonal - Hexagonal Scalenohedral 
Fracture
Brittle - Sectile 
Hardness
2-2.5 
Mineralpedia
View Proustite
On Dakota Matrix
Previously Sold Proustite
On Dakota Matrix
Other Available Proustite
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Mindat
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SOLD
Pseudobrookite - 61814
Pseudobrookite - 61814

Pseudobrookite

#61814
Locality
Topaz Mountain, Thomas Range, Juab Co., Utah, United States 
Formula
(Fe3+2Ti)O5 
Availability
Sold
Size
Micromount 

A choice specimen of Pseudobrookite with divergent crystals to 6mm on rhyolite matrix. Nicely mounted for preservation. Overall 2 x 1.5cm.


Pseudobrookite

Formula
(Fe3+2Ti)O5 
Crystal System
Orthorhombic 
Crystal Habit
Crystalline - Fine 
Cleavage
Poor, None, None 
Luster
Adamantine - Metallic 
Color
brownish black, reddish brown, black 
Streak
brown 
Class
Orthorhombic - Dipyramidal 
Fracture
Uneven 
Hardness
6 
Mineralpedia
View Pseudobrookite
On Dakota Matrix
Previously Sold Pseudobrookite
On Dakota Matrix
Other Available Pseudobrookite
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Mindat
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Pyrite - 61899
Pyrite - 61899

Pyrite

#61899
Locality
French Creek mines, Chester Co., Pennslyvania, United States 
Formula
FeS2 
Availability
Available
Price
$40.00
Size
Micromount 
Tagged
sulfide  

An old micromount with about 20 octahedral crystals to around 1mm.


Pyrite

Formula
FeS2 
Crystal System
Isometric 
Crystal Habit
Striated, Druse, Stalactitic 
Cleavage
Poor, Poor, None 
Luster
Metallic 
Color
pale brass yellow 
Streak
greenish black 
Class
Isometric - Diploidal 
Fracture
Conchoidal 
Hardness
6.5 
Mineralpedia
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SOLD
Pyromorphite - 61818
Pyromorphite - 61818

Pyromorphite

#61818
Locality
Bunker Hill mine, Shoshone Co., Idaho, United States 
Formula
Pb5(PO4)3Cl 
Availability
Sold
Size
Micromount 
Tagged
phosphate  

Prismatic-hexagonal cryrtals to 2mm. 


Pyromorphite

Formula
Pb5(PO4)3Cl 
Crystal System
Hexagonal 
Crystal Habit
Crystals short to long prismatic, acicular, often hoppered terminations, rarely tabular to equant; radiating to branching groups, tapering to a point. Commonly rounded, globular, reniform, botryoidal. 
Cleavage
On {1011}, interrupted 
Luster
Resinous to subadamantine 
Color
Dark grass-green, green, yellow, yellow-orange, reddish orange, yellow-brown, brown, tan, grayish, may be colorless 
Streak
White 
Geological Setting
A secondary mineral in the oxidized zone of lead deposits 
Class
Hexagonal, 6/m - Dipyramidal 
Fracture
Uneven to subconchoidal 
Hardness
3.5–4 
Mineralpedia
View Pyromorphite
On Dakota Matrix
Previously Sold Pyromorphite
On Dakota Matrix
Other Available Pyromorphite
WebMineral
View Pyromorphite
Mindat
View Pyromorphite

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